旋转振荡圆柱绕流中的频率耦合现象研究

Frequency coupling effect in flows around rotational oscillating circular cylinder

通过分离解法数值求解原始变量的不可压二维 N- S方程 ,对在均匀来流中旋转振荡圆柱问题进行了数值模拟 ,利用快速傅里叶变换 (FFT)方法进行频谱分析 ,得到了在低雷诺数下圆柱自然涡脱落频率同外部强迫振荡频率之间的耦合作用。进而说明了在不同频率耦合区域流场涡形成。

This paper presents numerical results of the flows around the rotationally oscillating circular cylinder by solving two dimensional N S equations. Using FFT (fast Fourier transfer) to study the frequency coupling effect, we get the results about coupling effects of the frequency of vorticity naturally shedding and the frequency of circular cylinder rotationally oscillating at low Reynold number. And we also show the regular patterns of vortex forming, developing and shedding.